It's the season 4 finale! What a whirlwind these past three weeks have been. Tonight on The Sing-Off, the final three groups perform two songs: one on their own and one holiday song with the judges. Reigning champs Pentatonix return to perform and mentor, and a winner is chosen. Plus, Pat Benatar, Neil Giraldo and 98 degrees all perform.

A beautiful and uplifting performance from the remaining three groups. Oh fun! The eliminated groups join in on the second half of the performance. They all sound great. It's fun to have them all back even though it has only been a week since they left.

Nick Lachey is going on about how Jewel has been a great addition and, oh man, he starts singing.

Nick Lachey & Jewel ("It Had to Be You")

Nick is being backed by the groups and it sounds great. The other judges are making her get on the stage. She joins him on the stage and sings along with him. This is adorable. I love the light-hearted camaraderie on this show. They all just have fun.

Ten & Shawn Stockman ("Joyful, Joyful")

Singing a the song from Sister Act 2 (amazing), Ten and Shawn blend together really well. His voice is still so amazing. Their tones and styles are very similar. I am mostly enjoying this performance because it reminds me of Sister Act 2. It's a fun performance and has a fun '90s flavor to it. Especially with those sassy Boyz II Men dance moves.

Pentatonix ("I Need Your Love")

God, they are just so good. They were hands down the best last season and this performance shows that they are always professional and amazing. Standing ovation from everyone, obviously.

Home Free ("I Want Crazy")

This professional a capella group was on tour before the show. They push themselves to be better with every performance and they have really grown over the course of the show. Pentatonix advises them to make winning moments happen in their arrangements.

Their sound is really full and varied in this performance, more so than any other performance. I don't know this song, but I love this version. The lead singer, Austin, has sounded shrill to me at times, but he really nails the lead vocal on this one from start to finish. Great arrangement, too.

Shawn tells them they have the type of sound the whole world would love. Ben comments on the awesome rhythm and that the song defied category. Jewel tells them that they performed like stars tonight.

98 Degrees ("I'll Be Home for Christmas")

Oh, this takes me back. Are they all dads by now? They all look like dads now. Which is great. They sound great, too. It's a busy arrangement, likely wanting to beef up their abilities among so many a capella groups, but overall it's fun. They are good sports.

Vocal Rush & Ben Folds ("The Little Drummer Boy/Peace on Earth")

I love Ben Folds. This is an adorable performance. I keep forgetting how young this group is, they sound so solid.

Ten ("Love on Top")

This team of former backup singers has so much soul and talent. I can't believe they never sang together before the show. Pentatonix advises them to rise to the occasion and have fun since it is the finale.

They look like golden goddesses. This is a difficult song to do a capella, there is so much groove to it. But they sound great, and the arrangement with the break-down is original and awesome. The lead vocal gets ahead of the beat a bit, but they get it back just as quickly. They change keys, like, four times during the break-down. They are clearly in it to win it as well.

Ben comments that they played with the groove well and did great. Jewel says that the lead vocal was so great, she wanted to spank her. She is always good for colorful commentary, that one. Shawn calls it a stank face performance, calling them professional and blessed.

Home Free & Jewel ("Have Yourself a Merry Little Christmas")

In a costume change, Jewel is clearly the star of this performance in the best kind of way. This is the best judges performance tonight. They blend so well together and sound awesome. I love that the guys can't stop looking at her with awe the entire performance.

Pat Benatar & Neil Giraldo ("We are Young")

A bit of a random performance, but it's cool to see Pat Benatar backed by all the groups. She sounds great considering this is the 35th year (how is that possible?) this song has been around. All kinds of reunions tonight.

Vocal Rush ("Roar")

This group of high school students are the youngest to ever make it to The Sing-Off finale. They have grown a lot since the premiere, but I have liked them from their first performance. They have a lot of maturity and depth to their performances. Pentatonix inspires Vocal Rush to work harder, given their success after winning last season.

It starts a bit rushed, they seem out of breath almost immediately. As it goes on, it gets better; they have so much potential. I can hear their youth and nerves in this performance, more so than any of their previous ones. It is good, but I am never swept away by it. Maybe it's the song choice.

Jewel comments that they pull the audience into their performances every time. Shawn sees their promise and their potential. Ben commends the lead vocals and tells them not to lose their energy in the future. All these comments seem like their different ways of telling them they aren't going to win.

And the Winner is...

The group in third place is Vocal Rush. Totally expected, but they have a bright future.

The winner of The Sing-Off season 4 is Home Free!

Also totally expected based on their popularity, but a well-deserved victory, nonetheless. These guys are great. I do hope to see more from Ten someday, too.

Another great a capella season is behind us. Hopefully, NBC will bring The Sing-Off back for a fifth season because it is just so much fun.